Analyzing Samples
Agilent Cary 630 FTIR Spectrometer User’s Guide 51
CAUTION
The windows are made of an infrared-transmitting material, ZnSe. ZnSe is a
relatively durable material, but can be easily scratched or damaged if too much
pressure is applied during cleaning or if an abrasive material is used. Materials
such as cotton swabs dipped in acetone are recommended for cleaning.
CAUTION
ZnSe is relatively chemically-resistant to materials with a pH range between 4
and 9, but there are some materials, such as strong acids or heavily basic
materials, that can harm ZnSe. Avoid having materials in contact with the ZnSe
window that are outside of this recommended pH range.
CAUTION
Do not break the spectrometer seal and attempt to clean interior surfaces.
Breaking the seal will void the warranty.
Collecting a background spectrum
For instructions on collecting a background using the software, refer
to the MicroLab PC Software User’s Guide.
NOTE
The background measurement should be taken at the same pathlength that the
sample will be measured.
CAUTION
To ensure an accurate background spectrum is collected, perform a visual
inspection of the ZnSe window surfaces looking for any haze or film present on
the windows from measuring the previous sample. If a film is observed, repeat
the cleaning procedure on Page 50 until the window surfaces are clear of any
residue.
Collecting a sample spectrum
To load a liquid sample and collect a spectrum using the DialPath
accessory:
1 Open the DialPath by rotating the arm (see Figure 14).